If you just wanted an entry for all group 1 values, you could do a 'left outer'. Assuming they are two different tables: your explanation is unclear.
For what you seem to want, I think you'll have to use a Mock-Crosstab. If you can't add a table, you'll be stuck with creating a 'Mock Crosstab'. Crosstabs are fine if you don't mind the absence of rows or columns with no data, but you said you wanted empty slots to show.
A 'Mock Crosstab' is something that looks like a Crosstab, but in fact you define each column yourself, normally as a running total. This would need to go in the report footer, because running totals count as the reports 'run' and they will not be complete until then. Crystal should have included an example along with the Crosstabs.
You can save a little time by doing a paste to a dummy report, changing the name and then pasting back. In Crystal 11.5, you can also duplicate formula fields using the Field Explorer.
Of course if all Group 1 and Group 2 values are certain to occur somewhere, a normal crosstab would show this.
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Madawc Williams (East Anglia, UK). Using Crystal 11.5 with SQL and Windows XP
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